Siemens SINAMICS G150, Operating Instructions Manual

Page: 482 / 680

Functions, monitoring, and protective functions
9.2 Drive functions
Converter cabinet units
482
Operating Instructions, 07/2016, A5E03347396A
9.2.1.3 Shortened rotating measurement
A normal rotating measurement cannot always be performed when the load is connected.
When switching on the motor for the first time, a moment of inertia measurement and the
measurement of the magnetization current and the saturation characteristic can be
performed with a simplified measuring procedure. There are two methods for this shortened
rotating measurement:
● Measurement shortened (p1959.12 = 1)
● After measurement: Direct transfer to operation (p1959.13 = 1)
During the shortened rotating measurement, the drive is not moved up to the rated speed but
up to the value set in p1965 (factory setting 40%). Parameter p1961 can be adjusted at the
plant, but it must be high enough to ensure that the machine has left open-loop controlled
operation. The machine should be operated in no-load operation (torque < 30% of M
rated
) as
far as is possible.
During the shortened rotating measurement the saving of parameters is disabled, because
parameter adjustments are automatically made for the measurement, which are to be
reassigned after the measurement.
Shortened measurement (p1959.12 = 1)
If p1959.12 = 1 is set, a shortened rotating measurement is carried out. In this case, the
magnetizing current and moment of inertia are determined with a somewhat lower degree of
accuracy; the vibration test is no longer required.
After the end of the measurement, the drive is moved to standstill and all the parameters
modified for performing the measurement are set to their original values.
After measurement: Direct transfer to operation (p1959.13 = 1)
If p1959.13 = 1 is set, the drive is not stopped after the end of the shortened measurement,
but is instead moved to the desired setpoint speed with the set ramp up.
Since braking to standstill cannot be performed during this measurement and no pulses are
locked, no more parameters can be changed that could later be written back during
operation.
Do not change controller parameters during the measurement (p1959.11 = 1)
With the rotating measurement, the drive independently changes its speed controller
parameters during start-up. This also occurs if bits 3 and 4 of parameter 1959 are not set. In
many cases, however, the decoupling of drives is linked to high cost. The loads have high
moments of inertia. The controller parameters set by the drive do not always match the drive
application and may therefore potentially cause damage to the mechanical system.
If p1959.11 = 1 is set, the recalculation of the speed controller parameters is prevented.